Abbott, based in Abbott Park, Illinois, contends Parsippany, New Jersey-based Watson is planning to market generic versions of the medicine before the patents expire, according to a complaint filed March 16.

Watson’s effort to sell the generic tablets “has led to foreseeable harm and injury to Abbott,” according to the lawsuit, which seeks a ruling of infringement and an order to stop Watson’s premature sale of the drug.

Abbott logged about $1.2 billion in U.S. sales of Niaspan in the 12 months ended Jan. 31, Watson said in a statement citing IMS Health data. Watson confirmed in the statement that it has filed an application with the U.S. Food and Drug Administration for approval to sell its version of the extended-release tablets.

The case is Abbott Laboratories v. Watson Pharmaceuticals Inc., 12-CV-324, U.S. District Court, District of Delaware (Wilmington).